1. Field of The Invention
The invention relates to a positioning device, more particularly to a device for adjustably positioning a rotary member at a desired angle relative to a fixed member.
2. Description Of The Related Art
FIG. 1 is an illustration of a window and window frame mounting arrangement commonly employed ih high-rise buildings. The window 12 is rotatable relative to the window frame 10 about a pair of axially aligned mounting posts 16a and 16b provided between the window frame 10 and the window 12. The two vertical sides of the window 12 are provided with lock devices 18a and 18b to keep the window 12 in the closed position. Referring to FIG. 2, to open the window 12, the lock devices 18a and 18b are unlocked, and the window 12 is rotated about the axis of the mouting posts 16a and 16b.
A main disadvantage of the above window and window frame arrangement is that the window 12 cannot be locked at the desired open position.